1. Field of the Invention
The present invention relates to a drum, and more particularly to a drum having a structure for adjusting the membrane to different tensions.
2. Description of the Prior Art
Typical drums comprise a membrane secured onto a cylindrical body. U.S. Pat. No. 4,330,124 to Vettorello discloses one of the typical drums and also includes a membrane secured onto a cylindrical body with a rim. However, once the membrane has been secured onto the cylindrical body, the tension of the membrane may not be easily adjusted.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional drums.
The primary objective of the present invention is to provide a drum including a structure for adjusting the membrane to different tensions.
In accordance with one aspect of the invention, there is provided a drum comprising a cylindrical drum body including a chamber formed therein and defined by an inner peripheral surface, and including an upper portion, and including an outer peripheral portion, a ring engaged in the upper portion of the drum body and engaged with the inner peripheral surface of the drum body, a membrane engaged onto the upper portion of the drum body, and including a peripheral skirt secured onto the outer peripheral portion of the drum body, and means for adjusting the ring to tension and to release the membrane. The tension of the membrane may thus be adjusted when the ring is tension or released.
The ring includes two edges, the adjusting means includes means for moving the edges of the ring toward and away from each other to tension and to release the membrane.
The moving means includes two blocks secured to the edges of the ring, and means for forcing the blocks toward and away from each other to tension and to release the membrane.
The blocks each includes an inclined inner surface facing toward each other, the forcing means includes a follower engaged between the inclined inner surfaces of the blocks, and means for actuating the follower to move relative to the blocks and to force the blocks toward and away from each other.
The adjusting means includes a screw hole formed in the follower, and a fastener engaged through the upper portion of the drum body and threaded with the screw hole of the follower, for moving the follower relative to the blocks when the fastener is rotated relative to the drum body.
The blocks each includes an outer portion having a groove formed therein for receiving the edges of the ring respectively.
The blocks each includes a base surface engaged with the inner peripheral surface of the drum body, and an end portion distal to the base surface thereof, the adjusting means includes a plate secured to the end portions of the blocks. The plate includes two ends each having a flap folded therefrom for engaging with the blocks respectively.